docs(stage2): reconcile S2-RO-10 Lab2 integration status

[Robinlee0929]

Summary

• Reconcile the canonical S2-RO-10 Lab2 documentation with the completed offline integration and hosted Safe CI evidence.
• Record the implementation commit, PR feat(stage2): make trusted runtime composition target-aware #90, merge commit and tree, hosted CI results, and accepted report-index warning.
• Correct the canonical integration-status identifier following independent review while preserving its COMPLETE value and all surrounding status content.
• Preserve the explicit boundaries that offline implementation authority is not live execution authority and source reachability is not execution authorization.

Scope

• Documentation only.
• Exactly two commits and one changed file.
• No source, tests, S2-RO-11 implementation, workflow, dependency, report, or integration-plan changes.

Validation

• Independent final read-only re-review: PASS with zero material findings.
• Cumulative git diff check: PASS.
• UTF-8, LF-only, no BOM: PASS.
• Fresh PR-triggered Safe CI is required before merge.

Safety

• No live Lab2 validation was performed or authorized.
• No credential, Owner approval, known-host, replay, socket, SSH, or RouterOS access occurred.
• S2-RO-11 Lab2 impact remains configuration-only.
• READY_FOR_LIVE_S2_RO_10_LAB2 remains NO.